Amido-stabilized rare-earth metal mixed methyl methylidene complexes

Abstract

Donor(thf)-induced tetramethylaluminate cleavage of Ln(AlMe(4))(2)(NSiMe(3)Ar(iPr)) as well as the reaction of (LnMe(3))(n) (Ln = Y, Ho, Lu) with HNSiMe(3)Ar(iPr) in tetrahydrofuran affords unprecedented trinuclear rare-earth metal tetramethyl methylidene complexes which act as Schrock-type nucleophilic carbenes and methyl transfer agents.

Syntheses, Structures, and Reactivities of Homometallic Rare‐Earth‐Metal Multimethyl Methylidene and Oxo Complexes

“…[17] All these complexes bear six-coordinate metal centers. To the best of our knowledge, this is the first example of a stable, solvent-free homometallic trinuclear tetramethyl rare-earth-metal methylidene complex.…”

“…Moreover, although these recent pioneering works show that methylidene complexes are endowed with a unique reactivity toward ketone, the resulting metal-containing products still lack full characterization. [9][10][11][12][13][14][15][16][17] We herein report a new synthetic pathway to aluminum-and solventfree homometallic trinuclear rare-earth-metal tetramethyl methylidene complexes with a bulky benzamidinate coA C H T U N G T R E N N U N G liA C H T U N G T R E N N U N G gand by means of C À H bond activation. We also describe their reactivity toward ketones, which leads to the isolation and structural characterization of some unusual polymethyl rareearth-metal oxo and mixed oxo/alkoxy complexes.…”

“…[16] Meanwhile, Mindiolas group reported another example of Lewis acid [9d] More recently, the homometallic THF-solvated methylidene complexes [{(2,6-iPrC 6 3 ] (Ln= Y, Ho, Lu) were reported by Anwanders group. [17] So far all these known rareearth-metal methylidene complexes are aluminum alkyl adducts formed through Me bridges or THF-solvated moleAbstract: Unsolvated, trinuclear, homometallic, rare-earth-metal multimethyl methylidene complexes…”

“…[1-8] Despite significant recent advances in this area, the chemistry of alkylidene/carbene complexes of rare-earth metals has only been explored in a limited fashion, [9][10][11][12][13][14][15][16][17] mainly due to the facile decomposition or oligomerization of such com-A C H T U N G T R E N N U N G pounds.…”

Holmium(III) Supermesityl-Imide Complexes Bearing Methylaluminato/Gallato Ligands

“…Potassium (2,4,6-tri-tert-butylphenyl)amide was synthesized according to literature procedures [7]. Homoleptic complexes [Ho{Al(CH3)4}3] [22,29] and [Ho{Ga(CH3)4}3] [30,31] (2) were prepared according to literature methods. DRIFT spectra were recorded on a NICOLET 6700 FTIR spectrometer (Thermo Scientific, Dreieich, Germany) using dried KBr and KBr window.…”